The present invention relates to an improved system and method for monitoring the movements and performance of a motor vehicle in order to locate the vehicle and determine the manner in which it is driven. A prior system for monitoring vehicular performance is described in U.S. Pat. No. 4,671,111 issued on Jun. 9, 1987, the entire disclosure of which is hereby incorporated by reference into the present specification.
In accordance with the present invention, performance variables associated with a motor vehicle are monitored by an onboard computer system. Such performance variables include the vehicle's speed, direction, and location. The vehicle's instantaneous accelerations in at least two horizontal directions are continually sensed and stored as coded signals in a computer memory by the onboard system. Performance variables of the vehicle are computed from the acceleration signals and stored in memory along with associated time and date codes. By means of inertial navigation using the accelaration data and/or radio transmissions from global positioning system satellites, the vehicle's global position is also computed and stored. The stored performance variables are analyzed over a period of time in order to evaluate how the vehicle is being driven. An evaluation code is computed which corresponds to an assessment of the current driving pattern. Such an assessment may indicate, for example, whether and how well the vehicle is maintaining a planned course of travel. Erratic driving patterns typically associated with driving under the influence of drugs or alcohol may also be detected. Warnings or other alerting signals to the driver are then generated by the system. The system may also output detailed descriptions of the performance variables and driving pattern either in the form of synthetic speech or a visual display.
The system also incorporates a shortwave radio transmitter/receiver for communicating with a remote monitor station. Performance variables and evaluation codes may be transmitted to the remote monitor station periodically and/or in response to a radioed request received by the onboard system from the remote monitor station. When an erratic or otherwise hazardous driving pattern is detected, signals may be generated to alert traffic authorities as well as informing authorities as to the vehicle's identity and location. Additionally, roadside warning signals along the vehicle's course of travel may be activated.
The system may also include brake and/or acceleration controllers for controlling the speed of the vehicle in response to the detection of a hazardous driving pattern. Activation of the controllers may be done by the onboard system automatically or in response to a radio transmission from a remote monitor station. The controllers may also be used to disable the vehicle in the event the vehicle is stolen, at which time the vehicle's identity and location may be transmitted to the authorities.
It is accordingly a primary object of the present invention to provide a system and method for monitoring the performance of a motor vehicle by an onboard computer system, which performance includes the vehicle's speed, direction, and location.
It is a further object of the invention to evaluate and record the performance of the vehicle over periods of time and generate evaluation codes indicative of certain driving patterns such as hazardous driving or compliance with a planned course of travel.
It is a further object of the invention to warn the driver when a hazardous driving pattern is detected.
It is a further object for the onboard system to communicate via short wave radio with a remote monitor station, transmitting performance data and evaluation codes to the remote station periodically and/or in response to a request from the remote station.
Other objects, features, and advantages of the invention will become evident in light of the following detailed description considered in conjunction with the referenced drawings of a preferred exemplary embodiment according to the present invention.